An image forming apparatus includes a developing device that contains developer. The developer includes a carrier and toner. The developing device supplies the toner as the developer onto a surface of a photosensitive drum, to thereby visualize an electrostatic latent image formed on a surface of the photosensitive drum. The toner is supplied by a toner hopper to the developing device. The toner hopper stores the toner and supplies the toner to the developing device.
Meanwhile, for filling the developing device with the developer, the toner hopper is removed from the image forming apparatus and a developer-supplying container is instead mounted on the image forming apparatus, for example.
A developer cartridge 300 as a typical developer-supplying container is shown in FIG. 8. A serviceman mounts the developer cartridge 300, which is filled with developer, on an image forming apparatus. The developer cartridge 300 is mounted on the image forming apparatus such that the developer cartridge 300 is located above the developing device and that an outlet port 304 serving as a developer-supplying port and an inlet port of the developing device into which the developer is fed are joined with each other. The developer filling a developer-containing section 313 of the developer cartridge 300 is stirred by a paddle 302 rotating about a shaft 310. The paddle 302 is rotated by power from a motor inside the image forming apparatus.
There is a conveying chamber 312 below the developer-containing section 313. The conveying chamber 312 includes an auger 303. The developer stirred with the paddle 302 flows down into the conveying chamber 312 by gravity. Note that, although not shown in FIG. 8, there is a partition between the developer-containing section 313 and the conveying chamber 312, the partition being opened on the front side of the drawing sheet. The developer flows into the conveying chamber 312 from the developer-containing section 313 through the opening of the partition.
By the auger 303 rotating about the shaft 311, the developer in the conveying chamber 312 is conveyed to the outlet port 304. The developer conveyed to the outlet port 304 falls by gravity and is supplied to the developing device located below the outlet port 304.
After the supply of the developer to the developing device is terminated, the serviceman removes the developer cartridge 300 from the image forming apparatus.
In a typical developer cartridge, the amount of developer supplied to the developing device depends on the amount of rotation and pitch of the auger. Further, the typical developer cartridge uses the auger serving as a developer-conveying mechanism. Therefore, depending on the amount of developer supplied to the developing device, it takes a lot of time to supply the developer.